Yes, I had one. It will work, but YOU have to put in a lot of hours training your pet. 1st you buy the system. The system runs about $150 to $200. 2nd you set up the system and put the electronic color on your pet. If your pet is fluffy you must shave the hair at the point of the contacts so it will make contact with your pets skin. 3rd You put your dog on a leash in the middle of the system. When he gets close to the line and his collar beeps, you yank him back. Do this repeatedly until when it beeps he jumps back on his own. If they continue over the line, they get shocked.
My dogs literally layed on the perimeter line, while being shocked, and exposed their tummmy for me to rub and make the shock go away. The other dog would bolt across the perimeter line, thus suffering little to no shock. I ended up selling mine for $120 and built a fence, it just wasn't worth it to me.
Either way, you must train the dog to obey your wishes.